1. Do Wrapped job setup with a diameter of your sphere.
2. Create the following vectors. I'm assuming wrapping x around y, so if your machine goes the other way, rotate 90 degrees. For this example I've assumed a 4" sphere. The vectors are a semicircle with a 4" diameter and two lines spaced 4" apart
3. Create a 2-rail sweep
4. The sphere has to be held in place by something while it's being cut. To do that, create a zero plane and give it a base height. I gave mine a base height of .25" which will leave a .5" spigot on the sphere. Set the combine mode for all the components to "merge". Here's a picture of what that looks like with toolpath wrapping turned on.
I'll leave it to you to toolpath it.
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